Sökning: "melting behavior"

Visar resultat 21 - 25 av 69 avhandlingar innehållade orden melting behavior.

  1. 21. Microstructural manipulation by laser irradiation of prepared samples : The ’Snapshot Method’

    Författare :Stephanie Robertson; Alexander F.H. Kaplan; Fredrik Sikström; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Produktionsutveckling; Manufacturing Systems Engineering;

    Sammanfattning : Various metallurgical microstructures and their formation are studied in this thesis by using a laser beam to melt a variety of materials with different chemical compositions over a range of thermal cycles. The laser beam was used conventionally in a narrow gap multi-layer weld, used for welding large depths with filler wire additions, as well as a non-traditional simulated welding approach labelled here as the Snapshot method. LÄS MER

  3. 22. Synthesis and properties of pi-conjugated polymers for organic photovoltaics

    Författare :Renee Kroon; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; organic photovoltaics; structure-property relationships; Conjugated polymers; energy level engineering;

    Sammanfattning : Organic photovoltaics is a renewable energy technology able to solve global warming and the upcoming energy gap, issues that both originate from fossil fuel consumption. Out of all renewable energy sources, the Sun is the only source that produces enough energy to fulfill all our energy needs, now and in the future. LÄS MER

  4. 23. Fuel conversion and ash formation interactions : a thermochemical study on lignocellulosic biomass

    Författare :Anna Strandberg; Markus Broström; Rainer Backman; Christoffer Boman; Maria Zevenhoven; Umeå universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Char conversion; pyrolysis; devolatilization; ash transformation; biomass; fuel characterization; fuel composition; ash composition; silicate formation; carbonate formation; thermogravimetric analysis; micro-tomography;

    Sammanfattning : Biomass is considered to be CO2 neutral, and to be able to reduce the dependency on fossil fuels the need for expanded and sustainable biomass feedstock is increasing. Ash-related problems are some of the most important aspects of this increasing use of new biomass assortments in thermal energy conversion systems. LÄS MER

  5. 24. Reactive Sintering of Cu-Al, Ni-Al and Ni-Ti Powder Mixtures

    Författare :Hossein Sina; Materialteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Sintering; In-situ microscopy; DSC; Intermetallic; aluminide;

    Sammanfattning : Intermetallic compounds are a distinct group of materials having attractive properties and wide applications. In the present work, the formation of intermetallic compounds from elemental components in Cu-Al, Ni-Al and Ni-Ti systems has been studied. Metallic powders were mixed in stoichiometric ratios corresponding to CuAl2, NiAl and NiTi. LÄS MER

  7. 25. Lignocellulosic residues for bioenergy : effects of storage, fuel design, and combustion characteristics

    Författare :Marjan Bozaghian; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES;

    Sammanfattning : Utilization of lignocellulosic residues for bioenergy raises storage, handling, and combustion challenges. The ash-forming elements in biomass may cause ash-related problems during combustion, such as slagging, fouling, corrosion, or bed agglomeration. Most of these problems are linked to ash-chemical reactions involving alkali. LÄS MER